1. Field of the Invention
This invention relates to a rotary cutter for a wood planing machine, more particularly to a rotary cutter including a polygonal shaft formed with blade-mounting surfaces for mounting of blades thereon.
2. Description of the Related Art
FIGS. 1 to 3 illustrate a conventional wood planing machine that includes a base 11, posts 12 standing upright from the base 11, a cutter carriage 13 mounted movably on the posts 12, and a rotary cutter 14 mounted rotatably on the cutter carriage 13. The rotary cutter 14 includes a shaft 15 that is formed with a plurality of recesses 153, and a plurality of blades 16, each of which is mounted securely on the shaft 15 and each of which is disposed in a respective one of the recesses 153. A pair of urging members 154 are disposed in each of the recesses 153 for adjustment of the depth of the blade 16 in the respective recess 153. A pressing plate 17 and screw means 19 are used for pressing the blade 16 against a mounting wall 155 of the shaft 15 upon adjustment of the screw means 19 to abut against an opposite wall 156 of the shaft 15 opposite to the mounting wall 155.
Since the recesses 153 are very narrow, tightening and loosening of the screw means 19 are relatively inconvenient during replacement of the blades 16.